BL-21671-140

Overview

The Knowles BL-21671-140 is a piezoelectric analog microphone designed for omnidirectional sound capture. It features a frequency response range of 100 Hz to 2.5 kHz and a sensitivity of -54.5dB ±3dB at 74dB SPL. The component utilizes solder pad termination and has physical dimensions of 7.87mm length, 5.54mm width, and 4.13mm height.

Feature Summary

• Omnidirectional acoustic port design for uniform sound pickup from all directions
• Piezoelectric transduction mechanism providing analog output signal
• Side-port configuration allowing flexible PCB layout integration

Applications

• Voice recognition systems requiring wide-angle audio input
• Consumer electronic devices with limited internal space
• Industrial monitoring equipment needing robust acoustic sensing

Procurement Notes

Verify the specific suffix code against official Knowles documentation to confirm exact sensitivity tolerances and terminal configurations. Ensure compatibility with existing PCB footprint dimensions before finalizing procurement orders.

Selection Notes

Select this model when omnidirectional coverage is required within a compact form factor. Consider the 2.5 kHz upper frequency limit for applications focused on voice rather than high-fidelity audio reproduction.

Part Context

This component belongs to the Knowles BL series of piezoelectric microphones. These devices are engineered for cost-effective mass production in consumer electronics while maintaining reliable acoustic performance standards.

Replacement Considerations

Consult official Knowles substitution guides for verified equivalents. Generic replacements may not match the precise sensitivity or dimensional constraints required for the original design.